but the links, hashtags and usernames are just coming back as text, so I had a look at the touchtweets example in the sdk and found the TweetListItemText.js file that is overriding the applyHtml function to covert them:

Code:

/**
* This is the component used in TweetListItem's to display the text of a tweet.
*
* This needs to be special so we can:
* - linkify URLs in the tweet
* - Wrap usernames with spans
* - Wrap hashtags with spans.
*/
Ext.define('Twitter.view.TweetListItemText', {
extend: 'Ext.Component',
/**
* We simply override the applyHtml method, which is called when the {@link #html} configuration is changed.
* We run a few regexs and try and match the URLs, hashtags or usernames, and then return the resulting value
* so the {@link #html} configuration can be updated (updateHtml).
*/
applyHtml: function(html) {
// replace URLs with proper tags
html = html.replace(/(http:\/\/[^\s]*)/g, "<a class=\"link\" target=\"_blank\" href=\"$1\">$1</a>");
// usernames
html = html.replace(/(^|\s)@(\w+)/g, "$1<span class=\"username\">@$2</span>");
// hashtags
html = html.replace(/(^|\s)#(\w+)/g, "$1<span class=\"hashtag\">#$2</span>");
return html;
}
});

Activate your top level component that you want to add the applyHtml function to.

Drag the Basic Function from the toolbox (Under Behaviors) to the top level component.
OR
Double click the basic function with the top level component activated
OR
Search for "Functions" in the property grid and click the +

After adding the function configure the name to applyHtml and the proper params.